Let Stannis and Roose battle. Let the enemies of the Throne slaughter each other and when they're done, seize Winterfell from whichever thief survives.

Littlefinger

They make a lovely couple. A Lannister and a Martell, they have no idea how dangerous that is.

Prince Doran

The High Septon has called for an inquest, not a trial. Just a small hearing to determine whether the charges against Loras have merit. Which I'm sure they don't. Loras will be freed, our happy alliance will continue. And we'll forget this unfortunate conversation ever happened.

Cersei

A girl is not ready to become No One. But she is ready to become Someone Else.

Jaqen H'ghar

Tyrion: How many centuries before we learn how to build cities like this again? For thousands of years the Valyrians were the best in the world at almost everything and then...
Ser Jorah: And then they weren't.

It takes courage to admit fear, and to admit a mistake. I came here to tell you that I was wrong. I was wrong and you were right about tradition. About bringing the people of this city together. I will reopen the fighting pits, to free men only. Slavery will never return to Meereen, not while I live.

Daenerys

Stannis: Lady Melisandre told me that death marches on the wall.
Sam: I've see it your grace.
Stannis: Seen what?
Sam: The army of the dead. And when they come...
Stannis: We have to know how to fight them. Keep reading Samwell Tarly.

Sansa: This isn't a strange place, this is my home. It's the people who are strange.
Ramsay: You're right, very strange.

You will find little joy in your command, but with luck you will the strength to do what needs to be done. Kill the boy Jon Snow. Winter is almost upon us. Kill the boy, and let the man be born.

Maester Aemon

Tyrion: You're going the wrong way. My sister's in Westeros. Westeros is west, we're heading east.
Jorah: I'm not taking you to your sister.
Tyrion: You said you were taking me to the queen.
Jorah: I am, to Daenerys Targaryen. She's the queen I serve.
Tyrion: [laughs] What a waste of a good kidnapping. So happens, I was heading there myself.

Melisandre: The dead don't need lovers, only the living.
Jon: I know, but I still love her.

Littlefinger: Stannis Baratheon garrisions at Castle Black. He'll march south to King's Landing before the winter snows block his way. But first, he has to take Winterfell.
Sansa: You don't know that.
Littlefinger: I do. Once he liberates these lands from the Boltons, he'll rally your father's bannermen to his cause. With the north behind him, Stannis can finally take the Iron Throne.
Sansa: You think he'll defeat the Boltons?
Littlefinger: He has a larger army. He's the finest military commander in Westeros. A betting man, would put his money on Stannis. As it happens, I am a betting man.

Game of Thrones Quotes

Tyrion: Let me give you some advice bastard. Never forget what you are. The rest of the world will not. Wear it like armor, and it can never be used to hurt you.
Jon: What the hell do you know about being a bastard?
Tyrion: All dwarfs are bastards in their father's eyes.

I will hurt you for this. A day will come when you think you are safe and happy, and your joy will turn to ashes in your mouth. And you will know the debt is paid.

Tyrion Lannister